1,618 research outputs found
In vitro percutaneous penetration of polycyclic aromatic hydrocarbons from sunscreen creams
Background: Dermal exposure to Polycyclic Aromatic Hydrocarbons (PAHs) affects many outdoor workers such as asphalt workers. Usually the use of sunscreen creams is suggested to protect them from UV radiation. However sunscreen could prevent or facilitate dermal absorption of industrial chemicals.
Objectives: The aim of the study was to assess percutaneous penetration of anthracene using 2 different sunscreen creams as vehicle.
Methods: In vitro permeation experiments were carried out using standardized in vitro methods with static diffusion cells. Excised human skin prepared to approximately 350 mm thickness was fixed on the diffusion cells. The receiving phase was a saline solution with 6% PEG 20. The 2 sunscreen creams (one lipophilic and one hydrophilic) were applied uniformly (2mg/cm2) on the skin mounted on the diffusion cell. After 20 minutes, a solution of anthracene and artificial sweat was added. Analysis of anthracene in the receptor samples was carried out by beta counter analyzer (Packard).
Results: Results did not show a percutaneous penetration of anthracene from sunscreen creams while in previous studies in vitro percutaneous penetration of anthracene was demonstrated using the same methodology.
Discussion and Conclusion: The use of sunscreen creams among outdoor workers, would not seem to enhance percutaneous penetration of PAHs. On the contrary it seems to be able to reduce dermal absorption of anthracene in the workplace
First CNGS events detected by LVD
The CERN Neutrino to Gran Sasso (CNGS) project aims to produce a high energy,
wide band beam at CERN and send it toward the INFN Gran Sasso
National Laboratory (LNGS), 732 km away. Its main goal is the observation of
the appearance, through neutrino flavour oscillation. The beam
started its operation in August 2006 for about 12 days: a total amount of
protons were delivered to the target. The LVD detector, installed
in hall A of the LNGS and mainly dedicated to the study of supernova neutrinos,
was fully operating during the whole CNGS running time. A total number of 569
events were detected in coincidence with the beam spill time. This is in good
agreement with the expected number of events from Montecarlo simulations.Comment: Accepted for publication by the European Physical Journal C ; 7
pages, 11 figure
On-line recognition of supernova neutrino bursts in the LVD detector
In this paper we show the capabilities of the Large Volume Detector (INFN
Gran Sasso National Laboratory) to identify a neutrino burst associated to a
supernova explosion, in the absence of an "external trigger", e.g., an optical
observation. We describe how the detector trigger and event selection have been
optimized for this purpose, and we detail the algorithm used for the on-line
burst recognition. The on-line sensitivity of the detector is defined and
discussed in terms of supernova distance and electron anti-neutrino intensity
at the source.Comment: Accepted for pubblication on Astroparticle Physics. 13 pages, 10
figure
Search for low energy neutrinos in correlation with the 8 events observed by the EXPLORER and NAUTILUS detectors in 2001
We report on a search for low-energy neutrino (antineutrino) bursts in
correlation with the 8 time coincident events observed by the gravitational
waves detectors EXPLORER and NAUTILUS (GWD) during the year 2001. The search,
conducted with the LVD detector (INFN Gran Sasso National Laboratory, Italy),
has considered several neutrino reactions, corresponding to different neutrino
species, and a wide range of time intervals around the (GWD) observed events.
No evidence for statistically significant correlated signals in LVD has been
found. Assuming two different origins for neutrino emission, the cooling of a
neutron star from a core-collapse supernova or from coalescing neutron stars
and the accretion of shocked matter, and taking into account neutrino
oscillations, we derive limits to the total energy emitted in neutrinos and to
the amount of accreting mass, respectively.Comment: Accepted for publication in Astronomy and Astrophysic
Study of single muons with the Large Volume Detector at Gran Sasso Laboratory
The present study is based on the sample of about 3 mln single muons observed
by LVD at underground Gran Sasso Laboratory during 36500 live hours from June
1992 to February 1998. We have measured the muon intensity at slant depths from
3 km w.e. to 20 km w.e. Most events are high energy downward muons produced by
meson decay in the atmosphere. The analysis of these muons has revealed the
power index of pion and kaon spectrum: 2.76 \pm 0.05. The reminders are
horizontal muons produced by the neutrino interactions in the rock surrounding
LVD. The value of this flux is obtained. The results are compared with Monte
Carlo simulations and the world data.Comment: 13 pages, 2 figures, accepted for publication in "Physics of Atomic
Nuclei
Lysine methyltransferase G9a methylates the transcription factor MyoD and regulates skeletal muscle differentiation
10.1073/pnas.1111628109Proceedings of the National Academy of Sciences1093841-84
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